How to reset the thermometer Xiaomi to factory settings: 5 proven ways

Xiaomi’s smart thermometers, from simple Mijia Bluetooth to advanced Aqara Temperature & Humidity Sensor, have become an integral part of smart home systems. But even the most reliable equipment sometimes has to be rebooted: after synchronization failures, when selling a device or if the sensor begins to give clearly incorrect readings (for example, the temperature of +80 ° C in a room). Unlike smartphones, where the reset is performed through menus, thermometers require a special approach – and here many users face difficulties.

In this article, we will discuss all the current reset methods for Xiaomi thermometers, including models with Bluetooth, Zigbee and Wi-Fi support. You will learn how to reset the settings through the Mi application. Home/Aqara, physical button (if any), and what to do if the thermometer stopped showing on the network after firmware 2026 We will focus on the typical errors that cause the reset to fail and give a checklist for the diagnosis of malfunctions.

1.When you need to reset the thermometer Xiaomi: 7 obvious reasons

Before you start resetting, make sure it is really necessary. Here are situations in which rebooting the device is justified:

• 🔄 Synchronization failure: Thermometer doesn't update data in Mi Home for more than 12 hours, even though battery is charged.
• 📱 Change of ownership: You sell or transfer the sensor to another user.
• 🌡️ Incorrect readings: the device shows deliberately false values (for example, humidity 0% or temperature below -50)°C indoors).
• 🔌 Problems after the update: the thermometer stopped working after an automatic firmware update.
• 🏠 Transfer to another home: sensor tied to old network Wi-Fi/Zigbee and not connect to the new.
• 🔋 Battery replacement: after installing a new battery, the device does not turn on.
• 🛠️ Preparation for repair: service center requires factory settings for diagnosis.

If your problem doesn't make it to this list, try reconnecting the thermometer to the app first or replacing the battery. Resetting is a last resort, because you'll have to reconfigure the device after that.

⚠️ Note: after resetting the thermometer Xiaomi Mijia LYWSD03MMC And similar models lose calibration of the sensors, if the device previously showed the temperature with an error. +2°C, after zeroing, the error may increase.

2. Method 1: Reset via the Mi Home app (for Bluetooth models)

This is the easiest method that works for most Xiaomi Bluetooth-enabled thermometers, such as:

• Mijia Bluetooth Temperature and Humidity Sensor (LYWSD03MMC),
• Xiaomi ClearGrass Temperature Sensor (CGG1),
• Yeelight Temperature & Humidity Sensor.

Instructions:

1. Open the Mi Home app and go to the Devices tab.
2. Find your thermometer on the list and tap it.
3. In the upper right corner, press three dots (⋮) and select the device settings.
4. Scroll down and click Remove the device (or Reset settings if there is one).
5. Confirm action. The thermometer will flash a red LED, signaling a successful reset.

If there is no Delete Device, your model does not support software reset, in which case use the physical method (see next section).

Make sure the thermometer is on and within range of Bluetooth

Check the version of the Mi Home app (current – no less than 6.5.4)

Disable VPN (it can block communication with Xiaomi servers)

Remember the current room settings (name, icon) for quick recovery-->

Method 2: Hardware reset (Reset button)

Some Xiaomi thermometer models have a hidden reset button.

• Aqara Temperature and Humidity Sensor (WSDCGQ11LM),
• Xiaomi Mijia LYWSDCGQ (old version with display)
• Yeelight Temperature & Humidity Sensor Pro.

How to find and use the button:

1. Remove the back cover of the thermometer (carefully tuck it with a plastic card or mediator).
2. Under the battery compartment, find a small hole with the inscription RESET or the icon of the arrow in a circle.
3. Take a paperclip or toothpick, press and hold the button for 10-15 seconds until the LED flashes red 3 times.
4. Release the button and wait for the reboot (it will take up to 30 seconds).

If the thermometer does not appear in Mi Home after reset, try:

• 🔋 Remove and insert the battery back.
• 📱 Reboot your smartphone.
• 🔄 Reinstall the Mi Home app.

Method 3: Reset via Zigbee Hub (for Aqara and Mi Zigbee)

Zigbee thermometers (e.g., Aqara WSDCGQ11LM or Xiaomi MJZNQ01LM) are dropped through the gateway.

• Aqara Hub (M1S, M2, Camera Hub G2H),
• Xiaomi Mi Zigbee Gateway (ZNDMWG02LM)

Step-by-step:

1. Open the Aqara Home app (or Mi Home if you use the Xiaomi gateway).
2. Go to the Devices section → Choose your thermometer.
3. Click Settings → Remove the device.
4. Confirm the deletion, the gateway will send the team to reset.
5. Wait until the LED on the thermometer starts flashing blue quickly (meaning the device is ready for a new binding).

If the thermometer is not reset:

• 🔌 Restart the Zigbee Hub (turn off power for 1 minute).
• 📡 Check the distance between the hub and the sensor (maximum 10 meters without obstacles).
• 🔄 Update the Hub firmware to the latest version.

5. Method 4: Resetting through AT-Teams (for advanced users)

This method is suitable for Bluetooth thermometers that support direct AT connection (e.g., LYWSD03MMC with Custom Firmware).

• Android smartphone with Bluetooth 4.0+ support
• The NRF Connect or Serial Bluetooth Terminal application
• Knowledge of basics AT-team.

Instructions:

1. Install one of the applications to work with Bluetooth LE.
2. Connect to the thermometer (it should be displayed as LYWSD03MMC or the like).
3. Send command: AT+RESET If the device supports advanced commands, try: AT+FACTORYRESET
4. Wait for the answer OK or the flashing of the LED.

⚠️ Warning: Infidels AT-If you're not sure what you're doing, you can use other methods to reset the thermometer permanently.

💡

Before shipment AT-Commands to check the firmware version of the thermometer. AT+VER. If the answer contains the word custom, then an informal firmware is installed, and the reset may work differently.

Method 5: Reset through battery discharge (extreme case)

If the thermometer doesn't respond to any commands and there's no physical reset button, you can try to empty the battery to zero, which works for most models, but it takes a long time.

How to do this:

1. Remove the battery and leave the thermometer without power for 24 hours.
2. Insert the battery back and immediately try adding the device to the Mi Home as new.
3. If the thermometer is not detected, repeat the discharge cycle again.

This method works in 70% of cases, but does not guarantee 100% results. If after 2-3 attempts the thermometer does not reset, most likely, the problem is in the hardware (for example, damaged memory chip).

⚠️ Warning: Do not use short circuits to speed up the discharge, this can burn the thermometer board.

7.Typical mistakes and how to avoid them

Even if you follow the instructions correctly, the reset may not work, and here are the most common mistakes and their solutions:

• 🚫 The thermometer is not detected in Mi Home after reset: Check if Bluetooth is turned on on on your smartphone. Make sure you are in the same region in Mi Home as when you first set up (e.g. Russia, not China).Reinstall the app and log in again.
• 🔄 Reset interrupted in the middle: Don't move further than 1 meter from the thermometer during the procedure. Turn off the power saving mode on your smartphone. Make sure the battery is not discharged (voltage should not be lower). 2.8V).
• 📵 LED doesn't blink after pressing Reset: Try holding the button longer (up to 20 seconds). Check if the battery contacts are contaminated (wipe them with alcohol). If the thermometer fell, the button plume may have gone away, you'll need to disassemble.

If none of these methods worked, the thermometer may have failed, in which case, contact Xiaomi’s service center or consider buying a new sensor — repairs are more expensive than the cost of the device.

💡

Always check the battery before reset, and a discharged battery is the most common cause of failed discharges (45% of cases according to service centers).

8 Frequently Asked Questions